Teachers play a vital role in their students’ educational performance. In addition, there is a correlation between a teacher’s experience and her effectiveness in the classroom—at least in the first few years of her career. These intuitive outcomes are supported by a large body of research literature. With this in mind, it is reasonable to view rising rates of teacher turnover (since the early 1990s) as a cause for concern. Further, the authors expect that retirements, which have driven some of this increase, will accelerate to record levels in the coming decade as growing numbers of baby boomers reach retirement age. This pattern will inevitably necessitate a significant increase in the demand for new teachers. Some communities—for example, poor urban districts, which tend to have especially high teacher turnover rates and severe recruitment problems—might be particularly susceptible to declining teacher quality as a result of increased retirements.